In conventional passenger cars and trucks, objectionable drive line vibrations may occur at certain speeds and load conditions. Some of these disturbances may be eliminated or reduced to an acceptable level by the incorporation of a proportional damper in the driven disk portion of the vehicle clutch. As is illustrated in U.S. Pat. No. 4,254,855, damping is normally provided by a plurality of circumferentially spaced coil springs, operatively connected between relatively rotatable elements of the clutch driven disk assembly.
Clutches which are currently utilized transmit relatively low levels of torque when in the release mode of less than 4 inch-pounds so that the clutches will function properly with the very efficient transmissions currently being manufactured. It has been found that free travel driven disk assemblies enable clutches used with highly efficient transmissions to function better. In free travel driven disk assemblies, damping springs do not engage immediately upon applying torque through the clutch but allow for slight lost motion. These clutches result in the hub assembly portion of the clutch being loose with respect to the support plate portion for the friction pads. Since the hub assembly is loose, it will rotate slightly with respect to the support plate when the support plate is urged against the flywheel during the engaged mode. This makes it difficult to insert through the clutch the splined input shaft from the transmission when installing the clutch in a drive train of the vehicle. This difficulty is exacerbated when there are two disk assemblies as is frequently the situation. In that free travel driven disk assemblies increase aggravation and assembly time for installers both on assembly lines and in repair shops, there is a need for a solution to the problem.